Can anyone give a more accurate timescale than 'later this year' with
regards to the release of the 64bit MAPI connector?
Which release version is it planned for?

It's planned for release with CGPro 5.4 by the end of the year, The code itself should be compatible with CGPro 5.3, but downloading a 64bit version of the server-side part requires extending the protocol, which can not v\be done in the 5.3 branch of CGPro. We hope to get the 64 bit variants of the client-side installer and the server-side dll in October - then it will be possible to test those by manually placing the server-side dll into system directories on the workstation.